Talk:Semi-trailer truck

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new info[edit]

I hope to soon write some pages from my 20 year experience as a (US) truck owner/operator. Some subjects would include: - maintainence and safety of tractor-trailers. - specification of componets (engines, transmitions, axles) when setting up a rig. - operating procedures for fair weather and foul. - size and weight laws in different locations. - loading and freight securement considerations for flatbed trailers. - Trucking in the extreme North end of N.America, and slightly beyond (on the oilfield ice roads)! Feel free to comment: Tim Coahran,


On some interstate highways in the US, long-haul semi-trailer trucks can tow another full trailer at the end, which makes the vehicle look like a two-car small train. Some of the second cars are full trailers with wheels on both ends, while others are just regular semi-trailer cars hooked to the standard coupling device on another set of wheels in tow (sometimes referred to as a "dolly"). There are proposals to allow a third car to be added to the vehicle, but they face strong objections from some car drivers who share the highway with these longer trucks.

The above paragraph makes it sound like triple-trailers aren't actually in use. They are, and at one time were pretty common on I-84 in northern Oregon. This has decreased over time — and additional permits are required for it — due to safety concerns (I've also heard it suggested that trucking companies may have found it to not be as economical as they'd hoped, but I can't speak to the veracity of those claims; insurance costs, perhaps?). Anyone traveling through the Columbia River Gorge still stands a decent chance of seeing one, though. -- nknight 10:17, 10 May 2004 (UTC)

I've certainly seen them on the Ohio Turnpike. I half-jokingly refer to them as "death trains". I've edited the paragraph to clarify that these are in use on some highways. --Arteitle 07:18, Sep 1, 2004 (UTC)

I think triple trailers are common in Austrailia (I understand that these "road trains" have the right of way over smaller vehicles). Also, the picture seems not as clear as would be that of a typical 18 wheeler, especially with a full on side profile. Leonard G. 00:03, 13 May 2004 (UTC)

European semi-trailer[edit]

In Europe, most semi tractors have 2 axles, again with the front, steer, having two wheels, and rear, drive, having a pair of double wheels on each side. Thus, the most common configuration has 6 wheels. Conversely, the cargo trailer usually has three axles at the rear, each with dual wheels, or 12 wheels in total.

I am confused by this description of the European trailer. If I read the description right, in Europe, the tractor only has two axles, and the cargo end has 3 axles. That means the cargo container is sitting on 12 wheels on the rear end and 4 wheels (rear of the tractor) on the front end.

Yes. I wrote that after traveling through several European countries and paying attention to this - I've almost never seen tractor with three axles. Nikola
I see plenty of triple axle tractors in the UK, but the centre one is almost always a lift axle - if that's the correct term. Mr Larrington (talk) 14:23, 28 April 2011 (UTC)
Here in Europe we usually don't have dual wheels under trailer. If trailer has 3 axles it usually means only 6 "super single" tyres. Tepo 25 September 2005

The weight of the tractor itself is distributed over the two front wheel and its own 4 wheels. ie. the middle 4 wheels are carrying both the load of the cargo and the engine. How does the weight distribution work? Assuming the weight of the cargo is distribute evenly on both ends, then the tire pressure on the road surface is quite lopsided. Since pressure = weight/area of road contact, the pressure these 4 wheels on the road surface is extremely high, theoretically 3 times those on the rear 12 wheels (1 axle supports the front end and 3 axles support the rear end of the cargo???). Probably strong enough to create a pot hole every couple of round trips. In the US, there are 8 wheels on each side of the cargo, hence the pressure and wear on the road surface is evenly distributed. Can someone in Europe explain the design philosophy behind such wheels arrangement? Does Europe trailers cause more road damage then their US counterpart?

I think that European trailers have their wheels moved more to the forward than American ones.
 o   oo          oo
 o    o        ooo

but it should be checked with appropriate legislations really. Nikola 11:20, 23 Jul 2004 (UTC)
Picture above is just like trailer tyres are under trailer here in Europe. Trailers axle positions are what they are becouse of legislation which say a certain circle which tyres aren't allowed to cut when turning sharply. When carrying small and very heavy pallets you have to put more cargo over trailers axle and leave some empty space in front of them. On typical 3-axle trailer-bogie you can put 24 metric tons. 2 axle tractor-unit usually has CGW of 18 metric tons. Tepo 25 September 2005
Isn't it true that when wheels of the three closely spaced axles make a turn, they require some kind of differential to prevent squeaking? Each of these wheels probably turn at a different pivot point. When the wheels are move forward, there will be considerable fishtail swing out to the opposite side of the turn. The article also mention the lack of nose on the tractor. The different driver position, the swinging tail etc. will make driving a truck quite different in Europe. Does US truck driver need additional training before driving in Europe? Kowloonese 17:28, 23 Jul 2004 (UTC)
sep 25, 2005 In theory the difference between a nose or a no-nose truck would be like the differense from an ordinary car to a van... I've been in a Scania 112 with nose (though the nose would be less than half length of many US trucks) and I didn't have any problems. When you have a drivers license here, you're supposed to control any vehicle in that category.
If You move to Europe on a permanent basis, I think You need to take a local drivers license anyway, I assume a number of theory lessons to see what your level is before the test, and eventually a driving lesson to check out local rule differences. G®iffen 10:43, 25 September 2005 (UTC)
Input from Denmark: Usually in DK we have Tractor/semi (t/s) 2 axles/3axles for lighter cargo distribution and for anything that goes thru Switzerland (due to special weight limits, eco-points and who knows what else...)
For heavy goods and usually for things going north or east, t/s is 3/3.
In general (VERY general) the rule would be 8 tons to the front axle and 9 tons to each rear. (Somehow it adds up to a max legal total weight of... 24????? tons for a 3-ax vehicle - no clue why). Normally each axle on the semi carries 8 t, and the king pin takes "the rest" adding up to the tractors total. I don't know the english word for the "thing" that locks the kingpin (and trailer) to the tractor, but nevertheless, its common that this thing can be moved towards back or front to optimize weight transfer between tractors front and rear axles.
By the way, "modern" trailers often have single tires, ant often 3rd axle on the tractor also have singles. On some tractors and semis the rear axle is steering to save rubber on the tires, and to make a smaller turning circle. Also european semitrailers often have thir wheels more to the front than the american semis I've noticed. Of course, we also have more old cities with narrow roads, haven't we? G®iffen 20:06, 5 September 2005 (UTC)

In Sweden the axle weight limits are 10 metric tons (11.5 for a driving axle) for single axles, 19 for twin axles, and 24 for tripple axles. Vehicles with 2 axles are allowed to gross 18 metric tons, 3 axles 26 tons, and 4 or more axles 32 tons. The exception is trailers which are allowed to gross 36 metric tons if the axle distance is more than 7.2 meters. The most common combination here is truck-trailers, the truck with three axles and the trailer with four, grossing 60 metric tons with a length of 24 meters. There are also a fair number of trucks with two trailers in a B-train configuration usually carrying shipping containers, one 20 ft and one 40 ft, which are allowed to be 25.25 meters. The same is true with trailers pulled by trucks using a dolly.

In Denmark "Søndagsavisen" from sep. 25, 2005 has an article on p.24 saying that the rules in DK "Are a lot closer to allowing 25,25m units of 60 tons in DK, starting with permission over Øresundsbron from Sweden to Kastrup Airport.
The Netherlands and Germany are testing at the moment, and Dansk Transport og Logistik (Transport organization) calculates 23-30 % savings on fuel by allowing (and of course using) the larger "module road trains" G®iffen 10:43, 25 September 2005 (UTC)
Road train in Finland

This is a typical (north)european tractor-semi combination, if you forget about the mid-axle trailer at the end. I assume 1. and 3. axle on the truck are steering axles, and this would be the only steering on the entire vehicle. G®iffen 20:04, 30 September 2005 (UTC)

I've never seen a tractor with a steerable rear axle, but it's common on 6x2 rigid trucks. The main advantage with it is a tighter turning radius, and less tire wear, but on a semi-trailer that doesn't matter much since they're mostly driven outside the cities. One of the trucks at work has a steerable rear axel and it definitely tightens the turns, but you've got to make sure there's nothing next to you when you start turning because the overhang can get pretty big.
In Denmark rear steering axles are quite common, both on trucks, semitrailers and buses. For some reason waste trucks often have steering on 2nd ax, while most other vehicles have it on 3rd.
For a test period buses are allowed with (somewhere around) 13,5 meters, if they have a steering 3rd axle. Normal max length for any vehicle is 12 m, except semis, which I think can be 13.6 m.
Another popular thing these years are so-called city-trailers, which means semitrailer with only one axle, where the steering makes it follow the track of the tractor. The system is also seen on 2-ax'd semis, with one or two steering axles.
Steering is normally shown in sales articles, i.e. Volvo 6*2/4 means volvo with 6 wheels, where 2 are drive wheels and 4 are steering. This system always count 2 wheels on one axle. If 6*2/2, usually you write 6*2. 6*6/6 wold probably be something armored from the military... G®iffen 16:44, 8 October 2005 (UTC)
Very common axle setup in Europe when it comes to local transport or heavier types of load
I have been watching the roads, and yes, in Denmark I see a lot of 2-ax tractors with 3-ax semi. Those usually look like export trailers. Another large group is the 3/3 combination on the photo. This is also normal when driving 40 ft shipping containers.

Type of trailers[edit]

I am always curious what each kind of trailer is designed for. The cargo container trailer is obvious. But there are some trailers that shaped like a funnel with a nossle near the bottom. Some look like liquid containers and some look like for gravels or something solid. It would be nice to have pictures of each type of trailers here in the article.
Or perhaps in trailer. Nikola 11:20, 23 Jul 2004 (UTC)
Trailer with hazmat, notice the different signs on the side. The large distance between the axles allows for a higher weight (10 tons per axle).
Volvo truck pulling a trailer that's larger than the EU standard. The last axle steers allowing for tighter turns.
    • On a similar note, it would be nice to explain how hazardous materials are moved using diferent kind of trailers. That has always intreged me. TomStar81 02:03, 7 Sep 2004 (UTC)
  • Tank trailers for powder or liquid.
  • Open or closed fladbeds for any cargo either solid or packed solid (ie. barrels, bales and pallets)
  • (Word unknown, tip or dump trailers?) for gravel, dirt, waste, stones, grain, debree etc.
    • Dump trailer, sometimes known as an end-dump trailer as opposed to a belly-dump or hopper
  • closed trailers with temperature control (freeze, cold or heat) for food and food products
    • Refer (more properly "refrigerated trailer")
  • special trailers for animal transport
    • Livestock trailer
  • (word unknown, pls insert) for heavy machines, macine parts, oversize loads
    • Low-boy
  • trailers for shipping containers
  • Different special constructions for specific types of cargo, e.g. automobile transport, timber etc.

G®iffen 16:57, 8 October 2005 (UTC)

    • I've interspersed my comments with yours. Also there's the Van trailer, which is the typical closed box trailer. Toiyabe 23:07, 19 April 2006 (UTC)

Article should be moved/renamed[edit]

I think this article should be named "Tractor-trailer". A semitrailer is a unit towed by a tractor and requies the fifth-wheel of the tractor to support the front. A full trailer, of course, is completely self-supporting, like a semitrailer/dolly combination. Rsduhamel 19:29, 6 Oct 2004 (UTC)

As far as I know, although tractor-trailer is the more correct term for a semi-trailer, most Australians and Americans would be unlikely to say "Tractor-Trailer" when referring to one. Any input from the rest of the world? --MartinRudat 09:07:56, 2005-08-30 (UTC)
I don't know about other places around the world, but in Australia, at least, if you were to say "Tractor-Trailer", the image that would come to mind would probably be a trailer pulled by a farm tractor. I only realised that "Tractor" is "Thing which applies Traction" rather than a farm implement after reading the article here on wikipedia. --MartinRudat 09:07:56, 2005-08-30 (UTC)
I had to read about a semi to know what it was, but I agree with MartinRudat about the farm tractor. Mainly because in Denmark the road tractor is called "trækker" - direct translation is "puller" as in pulling the trailer. By the way, semis are referred to as trailers in DK, while "your" trailers are called "påhængsvogne", translated something like "hook-on-waggons" because they are more or less fastened with a hook in the rear end. G®iffen 20:17, 5 September 2005 (UTC)
Well, I've heard the term "tractor-trailer" used among my coworkers quite frequently. But what do I know, I just used to drive them for a living. Rsduhamel 07:13, 5 May 2007 (UTC)

I think some or all of the information in the Construction section should be moved to the similar and more comprehensive Anatomy of a Truck section in Truck. Sticki 17:58, 20 September 2005 (UTC)

Article should definitely be renamed. As stated in the first paragraph, "a semi-trailer is a trailer without a front axle". The article then goes onto describe trailers (including front axles) and trailer (semi or otherwise) and locomotive combinations called variously articulated lorries, road-trains or otherwise. The semi-trailer is therefore a component of an articulated lorry - so either separate articles are required, or the article should be renamed. It makes more sense to name the article for the whole and then talk about the components, rather than - as at present - name the article for a component and then go onto to talk about other components and the whole. Anon.

:Since it is apparent from this thread and below's that both "semi-trailer truck" and "semi-trailer" have separate and specific meanings, and that the bulk of the current article should be under Semi-trailer truck, I have requested such a move. "Semi-trailer" specific text can then be extracted and returned to the freed-up Semi-trailer article space. ENeville 05:37, 9 September 2006 (UTC)

I would prefer an article name like Tractor-trailer truck (as a full name) over simply Tractor-trailer so as to make it clear we are talking about a type of truck, even though I understand most people in the business are too lazy to mention "truck" because the listeners in the business implicitly understand the talk is about trucks. Tractor-trailer could redirect to this this full name. Part of this problem is because there are many kinds of tractors and trailers, and tractor is hard to define exactly. I have no objection to the article staying at Semi-trailer truck. I do find the moniker "18-wheeler" to be an inaccurate name for all such trucks, because some do not have exactly 18 tires. I think 18-wheeler should be used for those that have 18 tires. H Padleckas 16:27, 8 July 2007 (UTC)

Definition of semi-trailer[edit]

This article didnt have a proper definition of a semi-trailer (apart from a vague etymology near the end) so I've replaced the etymology with a precise definition right at the begining where it aught to be so that anyone reading this article knows exactly what a semi-trailer is. It's worded as follows;-
"A semi-trailer is a trailer without a front axle. A large proportion of its weight is supported either by a tractor or by a detachable front axle assembly known as a dolly. A semi-trailer is equipped with legs to support it when it is uncoupled." Apgeraint 19:38, 12 April 2006 (UTC)

I agree that the title should be "Semi-trailer truck" instead of "Semi-trailer" because the latter refers only to the cargo segment while the former refers to the whole thing. If you want abbrev. probably "semi" suffices, but the article should have a more complete title. I actually am interested in an article that describes all the different kinds of semi-trailers found on the road. Some examples include the gasoline tanker, gravel loader, flat-bed for heavy equipment, cargo container, milk transporter, liquidifed gas tanker, timber hauler etc. Some photos to show how these trailers are used would be great. Kowloonese 01:46, 13 April 2006 (UTC)
May I suggest a gallery in the bottom? I'd like some different pics too, with "professional terms" describing the semitrailers G®iffen 12:51, 13 April 2006 (UTC)

I believe that the title of this article is absolutely correct This article is needed to define exactly what a semi-trailer is.
What is wrong with this article is that there are some elements in it not pertaining to semi-trailers. It would be better to put these in seperate articles.
There also seems to be a general lack of knowledge of the jargon (and of the exact meaning of some of the jargon). Since this is an encyclopedia, the correct terminology should be used and need to be defined as to their precise meaning. Maybe I'll sort this out when I get round to it. In the past 35 years I have trucked all round Europe and also travelled several times to the USA, Canada and Australia taking Photos of trucks and talking to truck drivers. One thing I have learned is that the jargon is exactly the same all over the English speaking world. It's only those unaquainted with the industry that use different words in different parts of the world since they don't know the correct terminology. Apgeraint 19:24, 13 April 2006 (UTC)

Please see Talk:Semi-trailer#Definition of Semi-trailer - comments please and provide feedback comments. H Padleckas 03:37, 13 July 2007 (UTC)

Authorized or vandalism?[edit]

Some ananymous user removed all about local differences. Is it vandalism, or did s/he put it somewhere else? I didn't like to rebuild it if there's a good explanation. G®iffen 14:53, 26 April 2006 (UTC)

Looking at the user's contributions, it doesn't look like the deleted information was put somwhere else. Seeing as the user is also Anon., I think that info should be put back. Toiyabe 15:19, 26 April 2006 (UTC)

What is this in english?[edit]


In danish, this is a blokvogn, but what do you call it? Is there an article about it, or is it just another semi? In da: I've started an article about it, and de: has one more or less about the heavy goods itself here - well, at least that's what my rusty german tells me. G®iffen 17:33, 13 July 2006 (UTC)

I've never seen a configuration like that in the US. Is that just a single tractor and a single trailer? If so it is officially a Class 10. If there's a dolly in there it would be a Class 13. Might be referred to as a "Permitted Vehicle" (i.e. it requires a special permit to operate as it will be overlength and/or overweight when loaded.)
Typically in the US you would see that sort of vehicle with one or more dollys up front, and maybe six split axles in the back (there's a picture of one at [1]. How does that thing turn? Do some of the axles on the trailer lift up (i.e. "tag axles"?)

Whenever larger than this, they usually have a lowered "middle" section and either

  1. a dolly (rare in Denmark) or
  2. a front end wheeled module

on the semi. But yes, technically this is a 5-axle tractor and 11 axle semi. Notice semiaxles 1,2,3,4 and 6 are airlifted. I believe that the driver can configure which semiaxle is "the not steering" and the others will track according to their position compared to the tractor and the locked axle. I don't remember if this had split axles (I assume that is "one axle in each side" instead of the same axle connecting both sides?)

The unit loads 240 metric tonnes plus the vehicle itself... Usually the total weight of any vehicle+trailer can never (legally) be more than 48 tonnes in DK.

Not to be commercial, but the company that owns the truck has an english homepage [2] with quite a few pics, showing their extremes. I didn't see any dolly-combinations. They like to use one brand of module trailers, that can be put together long, wide or in "blocks" of 2,3 or 4 axles extra according to the job.

I guess the banner in the bottom of this site illustrates "your" dolly combination?

Yeah, that's the sort of thing you usually see. Lift axles typically do not count towards the load rating in the US except on single-unit vehicles like concrete mixers and dump trucks. Toiyabe 18:32, 18 July 2006 (UTC)

Well, I find wisdom every day ;) Eh... Actually I just still need to know if there's a general term for overload vehicles in english? Above the shown one is called a class 10 or maybe class 13. I assume it is a (something) class 10 or 13, where "something" could be like heavy carriage, oversize vehicle or some other term covering all or most types of vehicles built for transporting items larger/heavier than the standard? As example the danish term blokvogn also includes mobile (wheeled) cranes over 32 tonnes and some other heavy or wide special vehic's. I did notice the term "permitted vehicle", but one can permit a lot of things for different occasions, right? G®iffen 14:58, 19 July 2006 (UTC)

I'm more familiar with the regulatory aspects. I've seen the terms "overweight", "oversize", "overdimensional" (covers oversize and overweight) and "permitted vehicle" (covers both oversize and overweight, maybe also some types of hazmats like nuclear waste). There's also the term "superheavy" which would refer to a vehicle that exceeds the bridge formula, and will require a specific load analysis for each bridge crossed. The regulatory terms vary slightly from state to state. There may well be a term used by truckers that is more specific to the vehicle itself, but I'm unaware of it.
Class 10 and Class 13 also include vehicles that are not oversize or overweight. A three axle tractor and three axle single trailer would fall into Class 10 (for instance a three axle dump truck and a three axle pup trailer). Rocky mountain and turnpike doubles would be class 13.
What's the translation of "blokvogn"? Big Wagon? Toiyabe 15:39, 19 July 2006 (UTC)

Blok is more or less the same as the english block (like a block of stone). Vogn is any unmotorized vehicle pulled by external engine or animal. It probably refers to carrying large rocks for building purposes (?) G®iffen 16:13, 19 July 2006 (UTC)

Well, last week I actually saw a dolly-setup for heavy load driving in Copenhagen. I think it was german or polish though.
Adskilt blokvogn 2.jpg
separated heavy load carrier
Lately I've seen two or three danish solutions where an extra axle is mounted on the tractor unit. One I saw had the semi separated for loading from front end of trailer, and two hydraulic cylinders over this extra axle would help holding the "Swan neck" (what ever it's called in english) seems it's called a gooseneck in english - the coupling from the fifth wheel to the load area. I'd wonder how these cylinders act while driving - if they transfer load to the extra axle or if it's just for the trailer separation. G®iffen 21:48, 8 July 2007 (UTC)

Would love stats![edit]

Hi! I came here looking for statistics on vehicle weight, cargo weight, and fuel efficiency. I was trying to calculate the cost and fuel efficiency of shipping goods via truck versus people in passenger vehicles driving to pick things up. Rummaging on Google I couldn't find anything with enough authority for me to add the numbers here, but if somebody finds those stats, they'd make a great addition to the article. Thanks, William Pietri 03:44, 17 July 2006 (UTC)

I found this article: which has some of the details requested by Billy above. You're welcome, Captain Milktoast 00:17, 10 March 2007 (UTC)Captain Milktoast

Rename the article?[edit]

Is this article about semi-trailer trucks (as titled)? Maybe I am reading this wrong, because I don't know this US English term first hand, but the title suggests that the article is about trucks insofar as they relate to semi-trailers. OK - I'm labouring this a little, but the article is (to my mind) titled about the truck itself (i.e. the prime mover or whatever else you want to call it). So what's all the stuff about trailers doing this article ? Trailer info is related useful info, but needs moving to somewhere else, no? Unless the article is retitled, that is. My preference is 'articulated lorry', but then, no doubt, others would say 'huh?' to that, just as I'm scratching my head about the current title. --!!!!

See section 4 on this page. (This is section 9) G®iffen 10:23, 9 October 2006 (UTC)
In Australia, the subject of this article is usually known just as a "semi trailer", and formally (in road laws etc) as an "articulated vehicle". The topic of semi-trailer would actually be called either just "trailer", or "semi-trailer trailer" if it needed the context. The thing at the front is called a prime mover when it is not towing a trailer. --Scott Davis Talk 09:22, 7 January 2007 (UTC)

About the Container King Sidepicker System In Canada-link[edit]

I was wondering if this link is OK or too commercial. Personally I would prefer to see it replaced by a video clip or photostring showing how a sideloader works? Besides it's uploaded by a user of the same name as the company... G®iffen 15:09, 20 October 2006 (UTC)

I've just removed all the external links as they appeared to be commercial. If there's something useful in one of them, it should be added to the text and use the website as the footnote reference. My quick scan suggested they all failed the External links guideline. --Scott Davis Talk 09:26, 7 January 2007 (UTC)

Trial in Germany[edit]

there are 3 different trials in Germany, one with only 40 metric tons, an other with 44tons and one with 60 tons maximum weight [Ecocombi#Deutschland] german wiki—The preceding []unsigned comment was added by (talk) 21:05, 24 January 2007 (UTC).

Trucking in Alaska[edit]

I used to drive a truck in Alaska, and in the winter it could get extremly dangerous. I would like to know if anyone else ever had the promblem of the suspension freezing completely while parked overnight. This made my truck incredibly unsafe. Please let me know if you has this problem. =]

Thankyou, kind regards,
Zesty Prospect 17:46, 31 March 2007 (UTC)


Why are they called "semi" trailers? Are they not full-sized trailers? —Ben FrantzDale (talk) 12:06, 19 December 2007 (UTC)

For some reason it's not explained before section 2.2 Construction. Somebody should put it up top somehow, but I'm not onto that at the moment... G®iffen (talk) 21:25, 24 December 2007 (UTC)
Yes, they are full-sized but do not "fully" trail. The designation "semi" refers to function rather than size. They are correctly called semi-trailers because they do not trail fully behind the prime mover, as a trailer does. This distinction leads to major design differences between trailers and semi-trailers. I'll try writing it in, near the top as suggested. Aboctok (talk) 19:13, 8 May 2010 (UTC)

Cab over the engine[edit]

In the United States: how come back in the 1970s and 1980s nearly all tractor-trailer trucks were built with the cab over the engine and steer wheels... yet during the 1990s and 2000s those disappeared, replaced by the engine and steer wheels being placed ahead of the cab? This seems to be a rather major change and I'm surprised it's not mentioned in the article. -Rolypolyman (talk) 12:02, 11 May 2008 (UTC)

Cab over trucks disappeared after the US length laws were relaxed. Originally the length law dictated a "bumper to bumper" length limit of 65 feet. It was later relaxed and allowed for the tractor to be of unlimited length as long as the over all length does not exceed the state laws (usually 75 feet). I don't exactly know when the law was relaxed but it was during the late 70's and drivers could not wait to get out of cab overs. They were largely perceived as uncomfortable and unsafe (driver is "sitting on the bumper" and first to arrive at a crash"). This is why cab over design came to a grinding halt and few if any changes were made to them after the early 80's. The most modern cab over that was available in the US/Canada was the Frieightliner Argosy which was popular with movers, curtain side car haulers and boat haulers. But the sales weren't enough and the Argosy was discontinued in 2007, an end to the sale of cab overs in North America. But some American made cab overs continue to be produced in Australia and New-zealand such as the Kenworth K104, Freightliner Argosy and the International 9800. I doubt they will ever appear again as there is little demand and a lingering stigma of their perceived comfort and safety (which is untrue of today's European cabovers). BUT Kenworth is producing off road only C500K cab over trucks with the DAF XF95 cab for oil field work. Thaddeusw (talk) 23:04, 12 March 2009 (UTC)
You still see a few cabovers in the US. For no readily apparent reason, about 95% of them appear to be hauling hay or straw. Mr Larrington (talk) 15:31, 8 December 2011 (UTC)

contrary to the former article[edit]

The statement "Contrary to the former article written on this topic, tandem setups are not restricted to certain roads anymore than a single setup. The exception are the units listed above. They are also not restricted because of weather or "difficulty" of operation.", sounds like an arguement that made it into the main article. At the minimum it does not sound encyclopedic nor up to wikipedia's standards. —Preceding unsigned comment added by (talk) 21:46, 30 July 2008 (UTC)

Rocky Mountain Doubles[edit]

The fifth picture in the article shows a truck with a full and partial trailer, calling it a 'Rocky Mountain Double.' This is an incorrect description as Rocky Mountain Doubles are trucks that haul 2 full trailers. This truck does have a double trailer, but if I am not mistaken, the term 'Rocky Mountain' refers to the fact that trucks with 2 full trailers are limited to operating in the Rocky Mountain states, whereas trucks like this one are allowed in most parts of the country. —Preceding unsigned comment added by (talk) 11:59, 6 September 2008 (UTC)

PowerRangers' trucks?[edit]

should it be mentioned that in some versions of the PowerRangers frnachise they use semis, in some cases for transport and such, and I think in other, the semi is actually one of the transforming giant robots? --TiagoTiago (talk) 21:01, 26 September 2008 (UTC)

why? What relevance does it really have to the subject of Semi's on the whole? BlakJakNZ (talk) 04:50, 16 October 2008 (UTC)

Semi-truck ,anufacturers[edit]

In this section there are two subsections "Used in the United States:" and "Used elsewhere:". What's so special about the USA? --Sigmundg (talk) 17:07, 18 December 2008 (UTC)

The USA has its own semi truck configurations and styles which are much different than European designs which have influenced other countries. For example The USA and Canada almost exclusively use conventional or "bonneted" trucks which are only sold in a few other countries such as Mexico, Australia, New Zealand and parts of South America. They have a different brake plumbing system (but mostly the same) and have 12 volt electrical systems as opposed to European trucks 24 volts. Another example is how Volvo tailored their NH cab for North America by adding longer sleeper options, different hoods and an all American made drive line and braking system with the only foreign parts being the Engine. The only thing a US Volvo and European Volvo have in common is the dash board and engine. Thaddeusw (talk) 23:18, 12 March 2009 (UTC)

Shunt trucks[edit]

In the middle, and very tiny on this photo we have the infamous "shunt truck". Also known as "shunter", "terminal tractor", "yard mules", "yard dogs", "goats", "hostlers", "shifters", "switches", "ro-ro tractors" etc.

Would it be worth mentioning here about Shunt trucks seeing as they dont have their own Article? Exit2DOS2000TC 09:09, 25 March 2009 (UTC)

Dunno. Never heard of them. --Athol Mullen (talk) 10:40, 27 March 2009 (UTC)
Thats not very helpful. I have heard about shunt trucks, or at least seen some. But I don't really don't know enough about them to write. Steinberger (talk) 17:04, 28 March 2009 (UTC)
I work across a large portion of the automotive industry and I haven't heard of a shunt truck. I had hoped that by commenting that I'd never heard of such a thing, someone might have provided at least a description of what they are supposed to be if not a web link. Otherwise, I'd probably have to assume that they were either a hoax or a local term for something which is known under some other name elsewhere. --Athol Mullen (talk) 01:43, 29 March 2009 (UTC)
I don't have any experience from the automotive industry nor am I a native speaker of english. However, one of the biggest manufacturers seem to be native to my homeland, namely Kalmar Industries and they are quite common here in Sweden. However, the term "shunt truck" seem to be very canadian and not all-english. Nevertheless, it reefers to the highly specialized tractors shunting trailers around terminals and harbors as seen in the picture. Steinberger (talk) 02:45, 29 March 2009 (UTC)
This is the type of Shunt truck I actually had in mind. Do others call it by a different name? The driver does not have to exit the vehicle cab to lift the trailers "standing legs" as the entire hitch point lifts about 9inches after being connected to the trailer, with the "standing legs" down. It is not really ment for Road use, just for "shunting" trailers from place to place in the yard. Quite efficient and strong, I have seen one pull a trailer with completely seized axle's. Exit2DOS CtrlAltDel 02:09, 10 July 2009 (UTC)

It's pretty hard to get around the transport industry and never see a yard dog, especially in intermodal rail-yards and around sea-shipping ports. A lot of larger terminals have the 'shunt trucks' Exit described, strictly for the purpose of switching -- it's a lot faster and usually they'll have a tighter turn radius than even a single-drive axle tractor.

Yard jockey, mule, dog, mutt, etc. are common names -- a lot of times, however, the same term is applied to a simple small tractor for dragging trailers around the lot and in/out of a shop.

The yard dogs I've seen and worked on also had a good deal of ballast on the rear drive axles for extra traction, and usually axle locks of some sort. Cheers (talk) 05:12, 12 February 2011 (UTC)

Oddly enough, this sounds like a North American thing. That sounds like its notable enough to me ... so started at Shunt truck. Feel free to add. Exit2DOS CtrlAltDel 20:25, 7 April 2011 (UTC)

Rearward Amplification: unwanted trailer oscillations[edit]

Nowhere in Wikipedia can I locate any reference to 'Rearward Amplification'. Suggest senior editors add this section. If you would like me to prepare this section, please let me know. Jeffrey Meade. --Sponsion (talk) 15:12, 17 May 2009 (UTC)

Here are four references: (1) Stability and Highway Damage Rearward amplification — a tendency of additional trailers to magnify even small amounts of sway, such as that caused by a blustery crosswind, even when driven by experienced drivers.

Rearward amplification is caused by the tendency of dual wheeled vehicles to resist turning.

(2) ...automatic brake control system that could intervene -- only when needed -- to help suppress unwanted trailer oscillations (commonly referred to as rearward amplification) in large combination vehicles (typically double and triple trailer combination). ...development and demonstration of a so-called "trailer-only" RAMS (Rearward Amplification Suppression) system.

(3) Sensitivity of rearward amplification control of a truck/full trailer to tyre (tire) cornering stiffness variations. Proceedings of the Institution of Mechanical Engineers -- Part D -- Journal of Automobile Engineering; 2001, Vol.

215 Issue 5, p579-588, 10p

Must use a library to access:

(4) Highway/heavy vehicle interaction

By Douglas W. Harwood, Commercial Truck and Bus Safety Synthesis 

...factors that contribute to increased lateral accelerations of the trailing units, the phenomenon known as rearward amplification, include the following:

id=mi9Sny62Qj0C&pg=PA18&lpg=PA18&dq=Rearward+Amplificatio n&source=bl&ots=XNrXvbPEW_&sig=dm_qcNQ-atHhbGfLU4P- Cqvx6QM&hl=en&ei=kRQQSvrBBYjMM6vd9FI&sa=X&oi=book_result& ct=result&resnum=2

--Sponsion (talk) 15:00, 17 May 2009 (UTC)

Transmission section contains false information[edit]

In the transmission section of the page it is explicitly implied that constant mesh non-synchro gear boxes (like those from Eaton-Fuller) must be double clutched to shift. This is completely untrue as you can easily shift them without using the clutch. Pretty much any gear box with no syncros can be "float" shifted. You need the clutch to stop and start but you float the gerars up and down (although flot down shifting takes some practice). This misinformation has been spread out for a long time, I mainly hear it from European truck drivers. Synchro gear boxes cannot be floated as the gears simply cannot be pulled out of mesh while under any torque, I know because I have tried it on a synchro fuller gear box, GMC 4 speed synchro and a 6 speed synchro ZF gear box in a Dodge Ram.

Also of note is a clutch brake is also not necessary but it helps allot when starting from a dead stop (its only use). Since there are no synchros to match the speed of the counter shaft to the main shaft, a special brake is installed on the input shaft behind the clutch. When the clutch pedal is fully depressed, it stops the input and counter shafts from turning allowing one to shift into their take-off gear of choice. The brake is a pain to replace so when it wears out most don't bother to replace it until clutch work is necessary (that could be upward of a half-million miles or more depending on the driver). So the best way to cope with a worn out clutch brake is to fully disengage the clutch, wait a few seconds and gently ease the stick into gear. Sometimes this produces a grinding sound, most likely because the driver didn't wait for the shafts to slow and is shifting into gear too fast (those are sloppy drivers IMHO). And on a side note: There is/was a clutch brake on some Fuller's that operated by a switch on the stick. It used an air cylinder to press a brake pad like device onto the side of an input shaft gear. So again a clutch brake is technically not necessary at all and many have out well over a half million miles on their gear boxes without one.

I began driving in a GMC 6000 with a 350 Chevy gas engine and 4 speed gear box. It was tough to learn shifting the first few minutes but I quickly got used to it. It was easy to shift without the clutch: you bring up the RPM's to the shift point, wind it up a bit more, let off the accelerator and the stick easily slid out of gear and into the next gear. Years later the top plate cracked and the transmission needed to be rebuilt. It was discovered that the synchronizers were all burnt out (By a previous driver). They rebuilt the gear box and it was terrible to drive. Constantly needing to hit the clutch pedal for each shift is annoying (that truck was gutless so you were constantly going between 3rd and 4th.)

I feel bad for the European drivers who are stuck with those awful synchro gear boxes. Why they think they are superior to constant mesh is beyond me, maybe they are jealous ;-). Thaddeusw (talk) 01:05, 7 August 2010 (UTC)

How does one imply something explicitly? That's a neat trick!
On a more serious note, you are welcome to rewrite the section to include information on floating gears, but such information needs to be sourced. The standard for inclusion on Wikipedia is not truth, but verifiability.
As for clutch brakes, the usual reason for them wearing out is because of inexperienced drivers pushing the clutch all the way down to shift while the truck is in motion. The clutch break has no chance with those kinds of forces working against it. Again, please find a source and improve the article accordingly. :) -Stian 11:57, 26 August 2010 (UTC) —Preceding unsigned comment added by Stian (talkcontribs)
The 'grinding' from trying to engage from a dead stop without a clutch brake is bad, and inevitable there is a good deal of wear and tear on the engagement mechanisms from it. You can get by without one, but they were invented with good reason - they're required for all practical intents and purposes.
A few of your other statements seem fizzy at best from my professional experience, but I'll try not to pick them apart too hard. While you can float a synchronous-meshed, the problem you get into is modern baulk rings will bite on the disengagement cycle if you don't remove enough of the torsional load from the keys on the synchro ring -- a gentle 'blip' if the gas and it should slip right out of gear, but it's more stubborn when you put a heavy load on it and the more keys on the ring. Multiple-ring synchros are even worse.
The Eaton/Fuller 6spd on a Intl. 4300 floats fine at 1200RPM, however, even loaded. I'm not sure if that's a unique case?
The reason your four-speed was such a charmer without them is probably the lack of modern-keying. Heavy-wear and tear on the synchros made their presence pretty much unnoticable; now, the gearbox tends to malfunction, even driven with a little more skill.
Cheers (talk) 05:07, 12 February 2011 (UTC)


Perhaps a little rewording on the use of the term 'tandem' is in order. Describing a trailer as having two tandem axles would mean it has 8 wheels...not such a common occurrence in my experience. Seems like the article has a lot of that ambiguity and poor terminology going on, however. (talk) 05:14, 12 February 2011 (UTC)

Underride guard[edit]

The second paragraph of this section looks very un-Wiki-like. Dkril (talk) 18:24, 13 February 2011 (UTC)

Where is safety/technology info?[edit]

Licensing is one part of safety. Engineering a system so it stops unless it's operating is another. I came to this article looking for information about spiffy safety devices like radar, eye cameras, or whatever might be out there. What about GPS? Surely there are truck versions of GPS that take into account restrictions on various routes. -- ke4roh (talk) 02:56, 19 July 2011 (UTC)

Please see Advanced driver assistance systems. —Scheinwerfermann T·C19:27, 27 August 2011 (UTC)

Why is it Called a "Tractor" Trailer instead of a "Truck-Trailer"?[edit]

I'm wondering where the use of the word "tractor" in this case, comes from. (talk) 19:06, 27 August 2011 (UTC)

"Tractor" and "Traction" have the same root. The idea is that the tractor is what supplies the pulling force. —Scheinwerfermann T·C19:26, 27 August 2011 (UTC)

Rear Wheels with Independent Steering[edit]

Truck hauling 36-Inch Pipe to build Keystone-Cushing Pipeline south-east of Peabody, Kansas, USA. The rear wheels on this truck has independent steering.

The rear wheels on this truck has independent steering, otherwise it wouldn't be able turn corners. • SbmeirowTalk • 21:42, 19 January 2012 (UTC)

Inconsistant terminology[edit]

Someone really needs to decide on one way to refer to the tractor/artic/prime mover/what have you--and then use it consistantly throughout the article. While hopping between them may feel inclusive, it is also somewhat annoying to read through and potentially very confusing. — Preceding unsigned comment added by (talk) 13:46, 5 June 2012 (UTC)


The Lithuanian interwiki points to lt:Automobilvežis, apparently an article about car transporters (trucks that transport cars). I don't think this link is such a great idea. But I'll refrain from attempting to remove the link, since helpful robots and humans would return it anyway. --Jmk (talk) 11:50, 7 June 2012 (UTC)


This article could stand some proofreading, preferably from someone who has gone beyond Pidgin English. DCDuring (talk) 18:13, 29 August 2012 (UTC)

20-05-2013 reword[edit]

A "truck and trailer" would be a strait truck pulling a trailer, not a semi. Where in the US is a semi called a "transfer truck"? "Mack" is a company name, not specific to semis, they make lots of strait trucks.

There is one wheel on each end of each axle, notes added.

Fraction implies a small part, doesn't it? With a "tandem" tractor and a two axle trailer, the tractor would carry close to half the weight, with a tandem tractor and single axle trailer the tractor could carry more than half the weight, with a single (rear) axle tractor and a two axle trailer the tractor could carry less than half the weight.

"with a strong internal beam connecting them to the cab" doesn't really make sense, does it?

Tires, eighteen wheels would be 9 axles.

Where do the feds restrict steer axle weight to less than 20,000#? 34,000# on the tractor tandem + 34,000# on the trailer tandem = 68,000#, leaving only 12,000# to the max gross of 80,000#, but you could still get there with 33,000# + 33,000# + 14,000#. If someone can find a federal (not state) law restricting steers to 12,000#, please put the second table back in.

Sammy D III (talk) 18:52, 20 May 2013 (UTC)

More rewording.
“The drive axles can be linked to provide more torque when higher traction is needed” is misleading. The idea of splitting the power between two axles may be difficult to understand, much less describe. In a tandem, all wheels drive all the time. There is another differential between the two axles, letting one go faster, so all four wheels can move at different speeds, avoiding tire scrub on tight corners. Same deal as an auto, only it works for four, instead of two, wheels. But only one tire has to spin to lose all power. The interaxle differential lock, when used, means both axles have to move at the same speed, so you have to spin one tire on each axle to lose power. You “lock ‘em up” on low traction surfaces, usually off road, but snow can do it, too. Driving on hard pavement, with no slip possible, strains the driveline and can break something.
The image of a “side dump” is actually an end dump. If you look closely you can see the vertical hydraulic cylinder on the front of the box. The curving bottom is structural (a curved plate is stronger than a flat one) and helps prevent the load from sticking when dumped. It's not side unloading, which we rarely, if ever, do. The length relates to bridge laws.
Side unloading is done on the U.S. west coast, example at dump truck. Sammy D III (talk) 20:43, 5 July 2013 (UTC)
The majority of tractors here have tandems, regardless of cab style.
Long winded, but it is a talk page, not an article.Sammy D III (talk) 13:41, 21 June 2013 (UTC)
The USDOT doesn’t restrict either the wheelbase or overall length (excluding auto and boat transporters, which are limited), other than to set minimums. A state can set limits only for vehicles operated intra(inside)state, excluding vehicles operated on the Interstate Highway System and reasonable access to it. The Feds measure wheelbase for bridge formulas only. See and How could you measure length minus cab, anyway?
In the past it was common for trailers to be restricted to 45’, overall length to 55’. The 10’ additional length for tractors was the reasoning behind COE tractors, which could then max out with a sleeper compartment. COE w/sleeper tractors are largely obsolete now.
Is there a reference for “most common trailer used in the North American is 53 feet (16 m) in length”? Although legal, observation would cast doubts on “most common”.
Yea, the section is about EU, but refers to NA, our turf.Sammy D III (talk) 15:48, 25 June 2013 (UTC)

Deletion tag removed[edit]

Hi. I have removed the deletion tag because a) I couldn't find any link to a discussion of the proposed deletion and b) because I sense the article is probably notable, but needs a cleanup rather than outright deletion. Views? --Bermicourt (talk) 11:47, 5 June 2013 (UTC)

Agreed. There is a lot of good info, and a fair number of refs, here. Plenty of editors stop by, and the view numbers are good, too.Sammy D III (talk) 13:41, 21 June 2013 (UTC)

Slang names[edit]

Actually, “double bottom” is in common use around here (Chicago). No idea where the “bottom” comes from, but it’s used. I have never heard of “a set” or “joints”, but I have never talked to a driver who drove one (only UPS uses them around here). I have never heard of a “dolly” called “con-gear”, but again, same qualification. This is all personal knowledge with no sources used now, but if someone can ref “joints” then I should be able to ref “bottoms”.

Transmissions are a mess. Macks come (came?) with 5 speeds standard. Where does “18 speeds” come from, a 5x4 has 20 total. I can think of no 18 speed combinations. (It is: 4 gears X 2 ranges = 8 speeds all split X 2 = 16 + low gear split X 2 = 18. Sorry Sammy D III (talk) 03:40, 11 July 2014 (UTC)). Transmission numbers often refer to useful ratios instead of total possible. A 9 speed is a 5 speed with 2 ranges, for 10 gears. 1st is Low and not used in road work, the rest are numbered 1-4 (low range) and 5-8 (in the high range Low is not used). 8 + Low make 9 useful gears. Similarly, a 13 speed (once the standard of road tractors) has 5 speeds with two ranges and a “splitter” (used in high range only), total 20 gears, 12 + Low makes 13 useful gears. A “Super-10” sounds like a 5 speed/2 speed, sometimes the splitter is in the transmission, but more often you have a “two speed rear end” axle split the gears. I can source many transmissions from a Mack Operator’s Handbook.

If anyone cares, I can help some, but do not intend to rewrite it myself.Sammy D III (talk) 15:37, 31 December 2013 (UTC)

In Transmission the word "constant mesh" is misused, it should be non synchronized. Constant mesh is an entirely different thing.Sammy D III (talk) 17:59, 31 December 2013 (UTC)

Side or rear underride guards[edit]

In addition to "underride guards" at the rear, I have occasionally seen what appear to be "side guards" on some high-quality trailers, presumably to help protect against fatalities in side collisions and jackknifing accidents. The lack of such guards in a collision is particularly dangerous, because the bed of the trailer is at a height where the first contact with a passenger car may be at windshield level. This completely bypasses the bumper and engine compartment crush zones, and may fail to activate protective air bags in any effective manner. I have seen some chilling photos of the aftermath of such a collision, and think that a less-gory photo of this would still be very instructive to readers.

Does anybody have information on US requirements for rear or side guards, "grandfathering" rules for older equipment, or NAFTA free trade rules? Also, my understanding is that EU and Japanese rules have been much stricter than the US rules for decades. Additional information on standards (or lack thereof) in the rest of the world would be much appreciated. Also, any statistics on the number and rate of underride collisions and fatalities would be useful. Thank you, in behalf of inquiring minds. Reify-tech (talk) 19:04, 31 December 2013 (UTC) has a lot of stuff, but is old. I couldn’t find anything better at the time. Are you sure you are not thinking about aerodynamic skirts (last paragraph in Trailers)?Sammy D III (talk) 19:56, 31 December 2013 (UTC)
It is hard to distinguish side underride guards from aerodynamic skirts by appearance alone, but I've heard that some safety standards require dual-purpose fittings. Thank you for what you were able to find quickly; there must be more information available somewhere, since truck manufacturers and users cannot be expected to follow rules that are not publicly available for all to see. Reify-tech (talk) 20:20, 31 December 2013 (UTC)
I was not aware that the feds had set side impact standards, I'll look around. The DOT must have it posted somewhere. That crash stuff is only crashes, not laws. I'm also going to check manufacture's sites, if they do anything, they'll brag about it. Interesting subject. Not sure when I'll be back, but I probably will.
Did you see the clips of the new Fed crash tests? Vicious right front impact, some can handle it. Long time since the '60's, when we started safety.Sammy D III (talk) 21:01, 31 December 2013 (UTC)

Federal vehicle standards are here: [3]. 224 is rear impact, but 214 side impact applies to under 10,000# GVW. Heil [4], HilBilt [5], and Utility [6] all sell new trailers with no apparent side impact equipment (Fruehauf's site is "under construction"). Are you sure standards exist?Sammy D III (talk) 21:53, 31 December 2013 (UTC)

Safety standards have been proposed in the US, but I have the impression that they've been repeatedly delayed (there were intermittent news reports on this issue). The only change I've noticed is the installation of retroreflective tape delineating the bottom edge of the trailer sidewall, which is better than nothing, but not much. I don't know much about researching EU, Japanese, or other world standards, but at least the EU publishes a lot of its material in English. Reify-tech (talk) 23:22, 31 December 2013 (UTC)
This table [7] may interest you. There is also an accident section at Truck.Sammy D III (talk) 00:10, 1 January 2014 (UTC)
I think this [8] may be it for Europe. I don’t care for these guys[9], but they do address this issue.Sammy D III (talk) 04:28, 3 January 2014 (UTC)

Notes: Axle, tire, wheel[edit]

Trucks are commonly measured by wheels, 4x2, 4x4, etc. This system has two wheels per axle, single or dual tires do not matter. Combinations are often counted by axles. Laws appear to always count axles.

Some US west coast over the road truckers said “eighteen-wheeler” for their 5 axle combinations, referring to the number of tires. Local slang, sort of. Movies have made this nickname common, but other than that, tires are not often counted. This can be confusing.

Crismon(01) explains the wheel system in detail, I think pretty much everyone uses it. It is (number of wheels) x (number of powered wheels). RSA shows single and dual tires are the same. US laws use axle, with no mention of single or dual tires. Duals are prohibited on steer axles. Sammy D III (talk) 03:42, 27 June 2014 (UTC)


Since there is some debate, I looked back through the logs, and sure enough: License, not licence, and the whole article was flushed out without using the word "lorry". It's in AmE, not BrE, please refrain from changing it back. Cheers, ~~ipuser (talk) 22:37, 22 April 2015 (UTC)

This should be reverted. Whilst the article probably was created in US English and so should generally use US English, it's also an international article with distinct sections on national variations. A UK section within that should remain in UK English. This sort of Emersonian "foolish consistency" is bureaucracy for the sheer sake of it. What's next? Describing how "big rigs" run down the A13 "freeway" to Southend? Andy Dingley (talk) 07:59, 23 April 2015 (UTC)
Well, we are supposed to stay consistent throughout an article, as has been stated many times. In this case, it means that when we start talking about semi-trailer trucks in the UK that they become lorries that ride on tyres. Notice that in the other sections, they aren't called "big rigs" or anything else, just "semi-trailer trucks". Your argument that something should be in british english just because the paragraph is about the UK is wrong, there's nothing special about Britain that lets it get a pass at ENGVAR. Sorry mate. ~~ipuser (talk) 05:20, 24 April 2015 (UTC)

Weight ratings[edit]

In the US "Gross Vehicle Weight Rating" (GVWR) is for a single vehicle. "Gross Combination Weight Rating" (GCWR) is for a truck or tractor with all trailers. The USDOT and these states use "combination" for vehicles and not "combined" for weight. [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28](defines GCW and GCWR) [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] (defines GCW and GCWR) [39] [40] [41] [42] [43] [44] [45] [46] [47]. [48] [49] [50] [51] [52] [53] [54] [55] [56] These three states [57] [58] [59] use "combined" describing weight, but refers to vehicles as "combination". Sammy D III (talk) 03:39, 30 June 2016 (UTC)

I just posted fifty-one rock solid refs for one word which probably won't be used anyway. An old-timer has told me that both words are acceptable and changed to the unrefrenced version, as well as other changes, without further discussion. Sammy D III (talk) 12:46, 12 July 2016 (UTC)
I'm really scratching my head as to why this is such a big deal. Both terms are used interchangeably worldwide. In the U.S., there is a favor toward using "combination" over "combined", while elsewhere in the world the use is also split but with a trend toward "combined". A quick Google search finds both phrases in use by both the USDOT and the NHTSA. Regardless, I've changed the article so your concerns will be assuaged. Huntster (t @ c) 14:03, 12 July 2016 (UTC)
Sorry, seems I forgot to press "Save page" a couple of hours ago. Something like: Wow, was that fast, thank you very much. I'm going to move one section down for dimentions. Thank you. Sammy D III (talk) 16:25, 12 July 2016 (UTC)

1 July 2016 reword[edit]

I changed the article to US English, it is tagged that way and I think “truck” implies US or Australia. It seemed a mixture of US English, UK English, and English As A Second Language. (EDIT: It was only tagged 22 April 2015)

I changed dimensions to US converted to metric. If source was US, I used that. If it wasn't I converted it to US, rounded that, then posted as US convert to metric. Many of these numbers are close, but not exact. I did meters to 1 past the decimal, maybe some should be two. Someone from a metric place might know.

I deleted a lot of stuff, but I think it was largely just words, not info. I re-arranged, then combined duplicate stuff. Mostly cut and paste, then smooth. I only added a little. I corrected and/or tried to make clear some individual facts.

I think that "Europe" should go into "Scandavia, Finland and the Netherlands" and "the Netherlands" should go into "Contental Europe", which could become only "Europe", or maybe EU.

For what it's worth. Sammy D III (talk) 03:42, 2 July 2016 (UTC)

Hello Huntster. A few questions. I don't know the difference in quote marks, but I will figure it out. I didn't think bold was right. - I don't understand numbers being "conversation", and the only change I made was to round them off. With the flip thing (I did see it) the first number, in English, converts to very odd numbers. I rounded to make a clear number only, and don't think I changed the meaning, just the flow. I think I only did it in that first Europe section, which I think should go anyway. Should there be two Europes? - In the Continental Europe section, all the sources are metric. The numbers should be English convert to (metric), but I thought in that section maybe we could sneak in metric convert to (English). That will be true to the source, and the first number would look good. I was thinking of not footnoting it, just doing it and see if anyone will notice. - You made the United Kingdom part of Europe, I don't understand that. The section only talks about England, nothing about the continent. I also think that "Denby" stuff should be cut back to maybe a paragraph or two, but somebody cares (cared?). - Farther down you changed a "GCWR", the second word is "combination", "not combined". I didn't (maybe won't) get that far.
I can't really change anything you have done (rounding numbers is my thought) because I have already been here so much it looks like "ownership". Have a nice day. (EDIT: This shouldn't be in the category "American Inventions", should it?) Sammy D III (talk) 12:17, 3 July 2016 (UTC)
Hi Sammy.
  • So first, our memorandum of style says that curly typographic quotes (“text”) should not be used, only straight typewriter quotes ("text").
  • I wrote "conversion" not "conversation". Regardless, Any input into {{Convert}} should be whatever a source states, rather than some kind of manual conversion as you did which has the possibility of becoming corrupted by other editors down the road. It's simply to make fact checking between article and sources easier. As for the "very odd numbers", can you give me an example of something that seems wrong? Very rarely should converted outputs be exact amounts (such as 90 tonnes [198,416 lb]), rather, significant figures are usually the way to go. I suppose an argument could be made here, but significant figures usually work best, which is why the Convert template uses them by default. I don't care if the entire article is one way or another (though I personally find the idea of using Imperial in material about Europe somewhat disconcerting), but I do want input numbers to be exact.
  • I don't understand the bit about me making the UK part of Europe. The United Kingdom is absolutely part of Europe, simply not Continental Europe, which is the reason I set the section headers the way I did.
  • Regarding the Denby stuff, if you can find a good way to condense the material, please have at it. It is a bit long for a relatively isolated thing.
  • For GCWR, both combination and combined are acceptable. Heck, this site uses both on the same page, and a Google search for combined yields 96,000 hits whereas combination yields 38,000 hits. The article for GCWR also gives alternate terms, which would also be acceptable. Not a big deal, honest.
I'm honestly not sure about the "American inventions" category. I know the box trailer and tanker trailer was invented by Fruehauf Corporation in the U.S., but I don't know enough about the history of semis to know what all came before. Huntster (t @ c) 00:59, 4 July 2016 (UTC)
The quotes must be from the word-processor, I will watch them.
If the source says 25.25 m. that comes out as 82.8 feet. That is a strange (odd) number, so I rounded to 83. (EDIT: we also use inches, so a decimal foot itself is noticibly odd). The flip deal will give 82.8 in the first place. Still, it is the source, I get that. (EDIT: I think I only did that in that first Europe section, which should be combined anyway).
England uses it's own measurements, money, laws, and is physically separated, I didn't think it was Europe. I do think of Scandinavia as Europe, maybe it isn't. I only cared about how many equals signs there should be around it.
I agree with Denby, but I don't want to cut someone else's stuff.
The US DOT uses "combination" and "combinations". The Illinois DOT uses "Vehicle or Combination". Neither actually uses the term in GCWR. I guess it's popularity.
I guess it is an American invention, I just thought it looked like US ego. I can't edit this article any more, but I want to thank you for your time, I have learned. Sammy D III (talk) 04:32, 4 July 2016 (UTC)
@Sammy D III: Ah yes, that's definitely the word processor doing it. I can understand the decimal foot being unusual, but it is pretty standard here. However, if you do want to use feet and inches, just use "ftin", as in "25.25 metres (82 ft 10 in)". I dislike it because it takes up so much more space and is relatively uncommon in use on Wikipedia, but there's nothing wrong with it. Yes, Scandinavia is part of Europe...Everything west of the Ural Mountains in Russia (including that part of Russia) down to (but not including) Turkey is considered Europe. Don't be afraid of editing others work! Once upon a time, the edit page said something to the effect of "If you don't want your contributions to be mercilessly editing by others, do not click the save button"! Hey, don't be worried about editing just because of the occasional perceived snag. I've been doing this since 2004 and have certainly run into my fair share. Don't hesitate to leave a note on my talk page if you ever have questions about things. Take care! Huntster (t @ c) 23:50, 4 July 2016 (UTC)

I think I have the dimention source problem solved, forest through the trees. Just do them manually, using the "&.nbsp;" thing. There aren't all that many. If the source is English the first digit is correct. If the source is metric, enter that in back and round the first digit. Or can you footnote each European section about units? I don't know how to make that look good, but it certainly is a thought. Opinion? Thank you very much. Sammy D III (talk) 14:37, 12 July 2016 (UTC)

I would urge you not to remove the conversions. They are specifically useful to show exactly what the citation says, and to ensure one or the other in the conversion pair does not unintentionally drift over time due to accidental and/or malicious editing. However, if you are concerned about the rounding thing, I would not be opposed to you using "0" to force exact measurements, a la {{convert|90|t|lb|0}} producing 90 tonnes (198,416 lb). I honestly dont like it, but meh, whatever. However, if decimal places are involved, I would suggest not rounding to whole numbers but instead using the "ftin" trick I mentioned above, if you feel that strongly about it. Huntster (t @ c) 20:41, 12 July 2016 (UTC)
Conversions, no rounding. I'm going to think about ftin, decimal feet just looks wrong to me. Do you ever see it in the outside world? I have been using lbs(kg), ft(m), and mi(km), similar size units that most of my sources use. I don't now what Europeans like, though. EDIT: It just doesn't work, the source number has to be first. I'm sorry I started this. I've asked before if we could use different systems per section and footnote it somehow? Then it could be source(ftin)? Sammy D III (talk) 21:45, 12 July 2016 (UTC)
Give me an example (just the code) of what isn't working. Regarding systems, pretty much the U.S. is the only English-speaking country that doesn't use metric. Huntster (t @ c) 22:47, 12 July 2016 (UTC)
I can't make myself clear. It is not code, it is trying to round numbers converted from metric to improve US English readibility. Switching system order, putting metric first, won't work. Rounding tons or large kgs to nearest pound seems resonable to me. I don't know what metric users want, kg or t. In length, breaking down to "ftin" is actually closer than decimal. How about: weight to the nearest pound, unit kg or t, and length foot/inch? That's what I have. If you don't like it, please say so and we can finish here, I've had more than a fair hearing now. Thank you. Sammy D III (talk) 02:06, 13 July 2016 (UTC)
Huh? You suggested removing the Convert template and manually converting them, and by one of your last comments, it's because "It just doesn't work, the source number has to be first"? Am I completely misunderstanding? Huntster (t @ c) 07:05, 13 July 2016 (UTC)
I was trying to make the article more readable, I thought the first number often looks awkward. The article is US, so US units should be first. Agreed? I just hate the source figure being in back. I think it looks like the first number is the source, and it is converted to the second number, opposite of the truth. Rounding makes the first number slightly more readable, but it is still a conversion, and doesn't look like it was set by any law or rule. We would make it even to start with, the conversion would have the fractions. First (actual source) number X and the second number converted to (Y.Z) You just can't use metric first, even though most of the article uses it as sources. I just can't stop the numbers from being accurate yet looking like shit.
I thought the numbers would be a simple project, I was wrong. I'm going to fix any damage I have caused, making the numbers the same value as before I got here. It will probably be more fun than wrecking them to start with. Let someone else mess with them. I'm really sorry I was rude and wasted your time for something that I just can't make work. EDIT: I can't change them back, you have changed some since then. Sammy D III (talk) 16:22, 13 July 2016 (UTC)

12 Jul 2016 reword[edit]

171,000 on 17 axles with only two trailers. Wow.

I am thinking of sorting and condensing Europe into UK, Continental, and Scandinavia. Each seems to have it's own conditions, and the article sort of breaks that way already.

North America has a sub-section Trucks, Europe has the same type of info in the front, it just isn't called Trucks. Shouldn't they be the same, and what should they be called?

Objections? Comments? If I do something I will try to do it in big pieces so it will be easy to revert.

Same deal, cut and paste, remove duplicate, smooth a little. Some sub-subsections were wrong, I removed them until someone can get them right. I think you need at least two, like an outline. I put dollies in Europe, behind truck info. I moved Semi-truck manufacturers to the bottom of Construction, I thought it belonged somewhere in there. A couple of small things that I can't remember, too.
Australia looks very good to me, I only moved super singles to right behind number of tires. I am not sure about paragraphs.
I took a couple of lines about hydraulics out of === Braking ===. I don't believe them, they are not referenced, and the hooking up of trailers is the important thing anyway. But if someone disagrees... Sammy D III (talk) 18:25, 27 July 2016 (UTC)


I am almost sixty years old, and I have never heard a semi-trailer truck called a "semi-truck." It can be a "semi" a "tractor," a "big rig," or a "truck." Where is the support or citation for "more commonly called a semi truck"? (talk) 16:13, 9 November 2017 (UTC)